Autogenous method of welding cast-iron.



ANDRE BELTZER AND UYRILLE DELCAMPE, OF BRIDGEPORT, CONNECTICUT.

AUTOGENOUS METHOD OF WELDING CAST-IRON.

Specification of Letters Patent.

Patented Dec. 29, 1908.

Application filed October 24, 1907. Serial No. 398,872.

To alZ wlto'rrz. it may concern:

Be it known that we, ANDRE BELTZER and CYRILLE lJELcAMPE, the former a citizen of the Republic of France, the latter a subject of the King of the Belgians, residing The present invention relates to an autogenous method of welding cast iron.

The attempt has been repeatedly made to weld together pieces of cast iron, but so far without success, and apparently because of the presence in cast iron of substances such as silicon, phosphorus, carbon, silica and sulfur, not to speak of other things in such quantities as to forbid or prevent the contact of the iron of the one piece with the iron of the other piece.

The object, therefore, of the present invention, is to produce a method which will act to remove welding preventive ingredients of castiron at the juncture.

To this end the invention consists in the method hereinafter described and particularly defined in the claims.

The best mode of practicing the present method is as follows: The surfaces of the pieces of iron to be Welded together should be cleaned by grinding, filing, or the use of emery cloth, or otherwise for the purpose of removing rust, and foreign substances. This is not, however, essential, for the reason that the very characteristics of the method by virtue of which it is possible to weld cast iron, render it unnecessary to clean the surfaces to be welded, and indeed it is one of the peculiar virtues of this process that this step need not necessarily be taken, as the process of welding eliminates such impurii ties as rust or other forclgn substances on the surfaces to be joined. For example, in the case of a cracked engine cylinder, where the portions tobe welded have not been entirely broken apart, access of course to the joint is impossible, but the Welding of the fracture may be accomplished without the cleaning of the surfaces. are loose and separate from each other, they should. be supported in proper relative posihere the parts tion to each other before beginning the operation of welding. Then the junctural portions of the pieces to be welded, that is, the portions adj accnt the juncture, are heated somewhat before applying the llux. lt is convenient to heat the junctural portion before applying the flux, because when the flux is applied it melts and adheres to the surface and runs into the interstice between them, but it is not necessarily essential, as the method may be practiced without such heating. Thereupon the junctural portions of the pieces are sprinkled with a flux powder having the property, when heated in contact with the cast iron to substantially the melting point of the cast iron, of substantially removing the welding preventive ingredients of the cast iron, that is to say, removing the welding preventive ingredients of the cast iron to an extent sufhcient to permit practical welding. The actual welding of the pieces together is now accomplished by heating the junctural portions of the cast iron to substantially the melting point. It is preferred during this heating operation to add cast iron to the joint, and for this purpose a rod or pencil of cast iron is dipped in the flux and presented to the heating flame where it is melted and flowed on to the joint, much in the same manner that solder is applied to a joint in soldering pieces of tin together, exce t, of course, that being cast iron, the coo ing process is so much faster that each portion of the joint must be finished as the hcat is advanced along it. The addition of the flux to the cast iron rod which is melted 011 a joint is for the purpose of refining the cast iron as it is applied to the joint, so that it will form a union with the pieces of cast iron to be welded, and also to bring some flux into the molten metal of the pieces to be welded but in its broader aspects the invention is not limited to the use of such added cast iron as under certain circumstances such addition might not be necessary.

Blow holes may be filled by the addition of cast iron in the above described manner, so also errors in workmanshi may be cured by adding cast iron to sur aces where too much has been removed, or, again, a protuberance may be formed by adding cast iron at any iarlicular place nhcre it is desired. A valuable feature of the invention consists in this, that when such cast iron is added to an original casting or piece, the added portion and its joint With the original iron are stronger than the original casting.

'lhe best flux for use in this rocess consists of a mixture of substantia ly 65% potassium chlorid, 15% lithium chlorid, and 20% potassium fluorid. 'lhe ingredients of the flux may be varied considerably. For example, a fluorid or chlorid of any of the alkali or alkali-earth metals may be used as a flux. Such a flux may be generically defined as an alkali-alkali-earth-metal fluorchlor-id flux. Experience demonstrates that the fiuorids and chloride of the alkali metals are the best flux ingredients for the ordinary grades of cast iron. ihe inclusion of some lithium chlorid in the preferred flux is for the purpose of making the substance deliquescent, so that when sprinkled on the junctural ortions it will adhere thereto as Well as to t e rod of cast iron when dipped in it. Calcium chlorid, another deliquescent chlorid, may be used in place of the lithium chlorid, but the latter is preferred because it liberates chlorin in the desired amounts, which assists in the elimination of the Weldin preventive ingredients of cast iron. 'lhe ch orids of the alkali metals are preferred to the chloride of the alkali-earth metals for the reason that they melt at a lower temperature, va orize more freely, and act more energetica ly in the Welding operation.

In case a fluorid alone is used as the flux the weldin is made With great facility and the joint 1s strong, malleable, and easily tooled but the existence of cavities in the joint, apparently caused by the excessive liberation of gases, to some extent weakens it. On the other hand, if a chlorid alone is used as the flux the joint is devoid of the cavities and is strong, tou h and so hard as to be tooled with diflicu ty. While the use of a fluorid alone, where the cavitation does not inhibit and the use of a chlorid alone, Where the hardness of the oint is desirable or immaterial are within the purview of the invention, it is referred to use a mixture of chloride and uorids as thereby a joint is secured Which is devoid of appreciable cavitation, strong, tough, capable of being readily tooled, and malleable.

It is preferred to make the flux of a very intimate mixture of the salts of which it is composed for the reason that when mixed intimately the mixture has a unitary melting oint. To this end the flux may be prepared by mixing concentrated solutions of the salts, evaporating the mixture to dryness and grinding the residuum, or it may be made by melting the salts together, taking care to use I as low a temperature as is possible in order to avoid decomposition of any of the ingredients, and then grinding the solidified mixture.

This invention is based upon principles which are not fully understood but it is ber lieved that the chemical reactions are somewhat as follows :Taking, for example, the action of the fluorid, which is believed to be typical of the action of the other salts, it is believed that the fiourid, with the water produced by the combustion of the flame used for heating, reacts with the silica contained as an impurity in the commercial fluorid used, and with the silica in the cast iron and with the silica produced by the combustion of the silicon contained in the cast iron, and forms metallic silicates which flow to the surface as a slag and fluor-hydric acid which attacks the other impurities of the cast iron.

In general it is believed that the o eration is based upon the aiiinity of the ha ogenids and the halogenid acids for the impurities of the cast iron.

'1 he means for heating the junctural portions of the metal is preferably an oxygenacetylene blow pipe by means of which high temperature may be secured.

Having thus described the invention, what is claimed is:

1. The autogenous method of Welding cast iron which consists in applying to the junctural portions of the pieces to be welded an alkali-alkali-earth-metal Iluor-chlor-id flux, and heating such junctural portions to substantially the melting oint of cast iron, substantially as describe 2. The autogenous method of Welding cast iron which consists in applying to the junctural portions of the ieces to be Welded a flux consisting of a mixture of alkali-alkaliearth-metal chlorids and fluorids, and heating such junctural ortions to substantially the melting point of cast iron, substantially as described.

3. The autogenous method of Welding cast iron which consists in applying to the junctural portions of the pieces to be Welded an alkali-alkali-earth-metal fiuor-chlor-id flux, heating such junctur'al portions to substantially the meltin Y point of cast iron, and adding cast iron and such flux during such heating, substantially as described.

4. The autogenous method of Welding cast iron which consists in applying to the junctural portions of the pieces to be Welded a flux having as an ingredient an alkali-metal chlorid, heating such junctural portions to substantially the melting point of cast iron, and adding cast iron and such flux during such heating, substantially as described.

5. The autogenous method of Welding cast iron which consists in applying to the junctural portions of the pieces to be welded a flux consisting of a mixture of alkalialkali earth-metal chloride and fluoride, heating such junctural portions to substantially the melting point of cast iron, and adding cast iron and such flux during such heating, substantially as described.

' tural portions of the 6. The autogenous method of Welding cast iron which consists in applying to the juncieces to be welded a flux consistin r of a mixture of substantially 80% alkali ch orids and 20% alkali fluorids, and heating such junctural. portions to substantially the melting point of cast iron, substantially as described.

7. The autogenous method of Welding cast iron which consists in applying to the junetural portions of the pieces to be welded a flux consisting of a mixture of substantially 80% alkali ehlorids and 20% alkali fluorids, and heating such junc-tural portions to substantially the melting point of cast iron, and adding east iron and such flux during the heating, substantially as described.

8. The autogenous method of welding cast iron which consists in applying to the junctural portions of the pieces to be Welded a flux having as an ingredient a chlorid of an alkali metal, and heating such junctural portion to substantially the melting point of cast iron, substantially as described.

9. he autogenous method of welding cast iron which consists in applying to the junctural portions of the 'ieces to be Welded a flux consisting of a mixture of substantially 65% potassium chlorid, 15% lithium chlorid and 20% potassium fluorid, and heatin the junctural portion to substantially theme ting point of cast iron, substantially as described.

10. The autogenous method of welding cast iron which consists in applying to the junctural portions of the cast iron a fiux, an

ingredient of which is a hi hly deliquescent alkali-alkali-earth-Inetal Cl1%OI'1d, and heating the junctural portions to substantially the melting oint of cast iron, substantially as described 11. The autogenous method of welding cast iron which consists in applying a flux acting to substantially remove the Welding preventive ingredients of cast iron, and heatmg the junctural portions to substantially the melting point of cast iron, substantially as described.

12. The autogenous method of Welding cast iron which consists in heating the junctural portions, applying a flux acting to substantially remove the welding preventive ingredients of cast iron, and heating the junctural portions to substantially the melting point of cast iron, substantially as described.

13. The autogenous method of Welding cast iron which consists in applying a flux acting to remove some of the welding preventive ingredients of cast iron, heating the junctural portions to substantially the melt ing point of cast iron, and adding cast iron and such flux during the heating, substan tially as described.

In testimony whereof We afiix our signatures, in presence of two Witnesses.

ANDRE BELTZER. CYRILLE DELCAMPE.

Witnesses:

H. T. PARROTT, R. C. SEELEY. 

